1. Field of the Invention:
The present invention relates to a system of detecting such behaviors of a charge as are difficult to be detected from outside of a metallurgical furnace or the like, including the movement, the rate of travel, fluctuations in the shape of the layer, and the like, of the charge put in the metallurgical furnace or the like.
2. Description of the Prior Art:
Generally, in the case of a furnace, typically a vertical metallurgical furnace like a blast furnace, ores, sintered ores, limestone, coke, and so forth are charged in the shape of layers in a sequential manner from the top of the furnace, then hot air and fuel are blown into the furnace from the lower portion thereof, to thus conduct refining. In such a case as this, it is quite important for conducting refining control of the furnace in a smooth manner to detect how the charge put in place from the top travels in the furnace, of what degree the rate of its travel is, what the distribution of its layers is like, and how the said distribution of the layers is subjected to fluctuations. However, the said behaviors of the charge has never been detected correctly enough, due to the reality that the said furnace is a sealed structure covered thick with refractory or steel and refining is conducted in quite high temperature. In the conventional practice, such a means as observes through television the shape of distribution of the surface layer of a charge at the top of the furnace, and such a means as learns the behaviors of a charge through detecting distribution of temperature or distribution of gases at the top of the furnace, have been developed and employed for the practical purpose, in an effort of learning the said behaviors of a charge. However, neither one of the said means can conduct proper detection of the behaviors of a charge below the stock line of the furnace. Therefore, control of reaction of the furnace by making use of the results of detection has been anything but high enough in terms of the precision thereof. In order to overcome the defect of insufficient precision of the above-mentioned indirect means of detection, such a means as learns the behaviors of a charge by detecting the magnetic force borne in ores by the use of a magnetic sensor has been contrived. One example of this category of means is disclosed in details in the Japanese Laid-Open Patent Gazette, No. 3,570-1973. The said method is such that a magnetoelectricity transducer element, a magnetometer, and a gaussmeter, well known as magnetic sensors, are arranged on the wall of the furnace, to thus detect the magnetic force generated from ores themselves and movement of a charge put in the furnace, also fluctuations in the state of distribution thereof, are to be detected through fluctuations in the magnetic force of ores formed by the movement of the charge thereof. However, this method is influenced a great deal by residual magnetism of the steel cover surrounding the furnace and by terrestrial magnesium, which makes it difficult to detect the magnetic force of ores, selected as an object of detection, in a manner of being separated from the said residual magnetism of the steel cover and the said terrestrial magnesium.